You'll need

1 litrepouring cream (40-50% fat content)120 gm (½ cup)crème fraîche

Method

01

Age the cream in the refrigerator until it starts to smell a little like it’s beginning to go off (1-1½ weeks). Transfer to a large bowl placed over a large saucepan of simmering water and stir occasionally so cream warms evenly to 37.5C on a thermometer or meets the pinkie test (see story).

02

Combine crème fraîche with 125ml warmed cream in a separate bowl, then add back to the cream and stir thoroughly.

03

Transfer to a saucepan with a tight-fitting lid, cover and wrap in a heavy blanket. Place in the warmest part of the house to inoculate (at least 20 hours). Unwrap saucepan, place in refrigerator and leave to age for 2 days and up to 3 weeks – at this stage you’ve made crème fraîche, the base for your cultured butter.

04

Transfer crème fraîche to an electric mixer and whisk on high speed until the cream splits (4-5 minutes). Reduce speed to low and beat until butter resembles popcorn and buttermilk splits out – this is when you should stop.

05

Strain through a colander. Reserve buttermilk for baking or marinating meat (it will keep refrigerated for up to 2 weeks).

06

Place colander in the sink or over a large bowl and rinse butter with well-chilled water, shaking occasionally and ensuring you don’t touch the butter with your hands, until water runs clear. You’ll have about 500gm butter.

07

Work the butter in a squeezing motion with your hands to remove excess water until it has the consistency of playdough.

08

Push it into a ring mould lined with greaseproof paper, fold paper to enclose, remove ring and secure with string if desired. Wrap in foil and plastic wrap and refrigerate for up to 3 months.

The starting point is very good cream. I look for organic, as
fresh as possible and with as high a fat content as I can find -
the ideal is 40 to 50 per cent. Farmers' markets are your best
go-to.

Ageing the cream is the next step. In this process we're trying to
grow lactobacillus.

As the pH drops, the cream sours, so taste every couple of days. I
age my cream in the refrigerator for a week until it smells like it
has turned slightly.

When the cream reaches the desired sourness, it needs to be
warmed to 37.5C to create the ideal environment for bacteria to
grow. When dealing with bacteria and culture, hygiene is very
important, so at this stage sterilise your bowls and utensils. Make
sure you wash your hands thoroughly before you continue or wear
disposable gloves.

Once this is done, heat the cream gently to prevent scalding, best
done in a double-boiler or bowl over a saucepan of simmering water,
stirring frequently to distribute the heat. Monitor the temperature
with a thermometer, or dip your little finger in the cream and
count to 10. If you can stand the temperature and only need to pull
it out at the count of 10, you've hit the sweet spot. If it remains
cool, give it a little more time and test again. Too hot and you'll
need to let the cream cool a little (up to 45C is fine).

At this point, add the lactic culture, either in crystal form
(available at cheeselinks.com) or in the form of active
crème fraîche or live buttermilk, which functions a bit like a
mother or starter in sourdough-making.

Check the ingredients of whatever crème fraîche or buttermilk you
intend to use - it needs to have active lactic culture. Much of the
buttermilk available is not live buttermilk; rather, it's a
combination of skim milk, skim milk powder and culture. Farmers'
markets are a reliable source of the real deal.

As a general equation, I add half a cup of culture for every litre
of cream. When the culture is first introduced to the warm cream,
it eats the lactose and converts it into lactic acid.

Once the cream is inoculated, a stable temperature of between
20C and 37.5C needs to be maintained for at least 20 hours. At
home, the best way to do this is to place the cream in a saucepan
with a lid and wrap it in a thick woollen blanket. Place the whole
bundle in the warmest part of the house where it won't be
disturbed.

Next, the mixture needs to set in the fridge for 24 hours (unwrap
it first) - the mixture will resemble thick custard. You've just
made crème fraîche.

Beat the crème fraîche on high speed in a heavy-duty electric
mixer fitted with a paddle attachment until it thickens and splits;
it will develop a slight yellow tinge and spray out buttermilk.
Reduce to the lowest possible speed and keep beating until the
butter comes out of the cream and starts to resemble popcorn. This
is where the fat content of the cream comes into play - if you've
used cream with 50 per cent fat, you'll have about half buttery
solids and half buttermilk.

Tip all the mixture into a colander over a large bowl and
refrigerate the buttermilk in a sterile container for up to two
weeks.

The butter "popcorn" then needs to be rinsed of any remaining
buttermilk. Place the colander in the sink and pour about a litre
of chilled water over, shaking the colander until the water runs
clear.

Next, knead and squeeze a handful of butter at a time to extract
any remaining liquid until the butter feels like playdough. Push it
into a ring mould lined with baking paper, fold the paper over to
enclose, then wrap in foil and plastic wrap. Refrigerate in an
airtight container for up to three months.

At A Glance

45 min preparation (plus ageing, culturing, setting)

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